People whose partner stops smoking, loses weight or gets more active are far more likely to succeed in adopting healthier habits themselves

Quitting smoking, getting fit or losing weight are all easier if your partner is on the same health kick, new research suggests.

People whose partner stops smoking, loses weight or gets more active are far more likely to be successful in adopting healthier habits themselves, according to a study that compared people trying to get healthy at the same time as their partner or separately.

By contrast, living with somebody who is not overweight, does not smoke or plays sport regularly does not appear to help you change your own behaviour, according to the study published in the journal JAMA Internal Medicine. But if your spouse or partner manages to turn over a new leaf, it improves your chances of doing so too.

A large body of evidence suggests that people adopt the sorts of behaviour they see around them – and in particular that of their spouses. Couples tend to have similar drinking, smoking, physical activity and eating patterns. Some of the similarity, say the researchers, “appears to be the result of assortative mating, with individuals selecting mates with behaviours similar to their own”.

But people are also more likely to change their behaviour if their partner does. “For example, people are substantially more likely to begin smoking and less likely to quit, if their partner smokes,” say the authors.

Among women who smoked, 50% managed to quit if their partner gave up smoking too at the same time, compared with 17% of women whose partners were already non-smokers, and 8% of those whose partners continued to be regular smokers. Among men, 48% managed to stop compared with 8% who were living with a regular smoker.

Two thirds of men and women managed to become more physically active if their partner did, compared with a quarter of people whose partner remained inactive. The figures for weight loss were not quite as marked – 26% of men lost more than 5% of their bodyweight if their partner did, compared with 10% of those whose partner did not attempt to change, while 36% of women hit the target if their partner did, compared with 15% of those whose partner remained the same weight.

“We found that men and women are strongly influenced by their partner’s behaviour in relation to making health behaviour changes,” say the authors. “Individuals whose partner’s behaviour became healthy were significantly more likely to improve their own behaviour than those with a partner who was always healthy. This suggests that people may be more successful in changing their behaviour if their partner does it with them.”

Professor Jane Wardle, director of Cancer Research UK’s Health Behaviour Research Centre at University College London and one of the study authors, said: “Unhealthy lifestyles are a leading cause of death from chronic disease worldwide. The key lifestyle risks are smoking, excess weight, physical inactivity, poor diet and alcohol consumption. Swapping bad habits for good ones can reduce the risk of disease, including cancer.”